One of the crucial factors affecting the performance of a compressor is its mechanical efficiency. For example, the reciprocating piston-cylinder compressor exhibits good mechanical efficiency, but its reciprocating action results in significant vibration and noise problems. To negate such problems, rotary compressors have gained much popularity due to their compactness in design and low vibration. However, as their parts are in sliding contact and generally possess high relative speeds, frictional losses are high. This has limited their efficiency and reliability.
In rotary sliding vane compressors, the rotor and vane tip rub against the cylinder interior at high speeds, resulting in large frictional losses. Similarly, in rolling-piston compressors, the rolling piston rubs against the eccentric and the cylinder interior thereby resulting in significant friction losses.
If the relative speeds of the contacting components in rotary compressors can be effectively reduced, their overall performance and reliability may be able to be improved.